This invention relates to a liquid containment device with a self-contained pump for dispensing liquid in small doses of a predetermined volume. More particularly, this invention relates to a replaceable containment device of the foregoing character that is useful in an ink-jet printer for containing a supply of printing ink and for dispensing the printing ink to a printing head upon the actuation of the self-contained pump.
A pending U.S. patent application filed by Bruce Cowger and Norman Pawlowski, Jr. for an invention entitled xe2x80x9cInk Supply For An Ink-Jet Printer,xe2x80x9d describes an ink supply for an ink-jet printer that is separate from the printer ink pen, and can be replaced upon the emptying of the ink supply without the need to replace the printer ink pen. The ink supply of the aforesaid U.S. patent application incorporates a self-contained pumping device for dispensing ink from a pumping chamber, and describes, as an embodiment of such a pumping device, a bellows pump. However, a bellows pump requires a relatively large extended surface of a semi-rigid material, such as a polymeric material, and is subject to a relatively high rate of oxygen and moisture transfer through the material of the bellows. This oxygen and/or moisture transfer can result in the degradation of the ink within the ink supply, especially in a printer that is used only infrequently. Further, the bellows is subject to leakage at the location of its attachment to another portion of the ink supply. According to the aforesaid pending U.S. patent application Ser. No. 08/429,987, these and other problems associated with the use of a bellows can be avoided by the use of a pumping device having a rigid perimetrical wall, preferably formed integrally with the associated chassis structure of the ink supply, with a linearly acting pumping member that is moveable within a pumping chamber defined by the rigid wall to pressurize ink within the pumping chamber, and a flexible moisture and oxygen barrier film heat sealed to an edge of the perimetrical wall in a continuous pattern and overlying the pumping member.
An ink supply according to the aforesaid U.S. patent application Ser. No. 08/429,987 also has a generally cup-shaped outer shell of a fairly rigid polymeric material, preferably a material with translucent properties to permit inspection of the contents thereof, which is used to contain and protect a flexible, ink-containing pouch. The outer shell is generally rectangular in cross-section, with an opposed pair of very long sides and an opposed pair of very short sides, the configuration of the shell being determined by the design of a docking station of the printer into which the ink supply is to be inserted when it is in position for the dispensing of ink therefrom. In such an arrangement, it has been found to be desirable to encircle the ink-containing pouch within a perimetrical frame whose sides have sufficient rigidity to protect the ink-containing pouch from impact and shock loads. The perimetrical frame, however, occupies space within the outer shell unless the frame and shell are so designed, in accordance with the present invention, that portions of the legs of the frame project into, or through, adjacent portions of the outer shell.
In an ink supply according to the aforesaid pending U.S. patent application Ser. No. 08/429,987, there is also provided a chassis to be affixed to the open end of the shell. This chassis, which houses the pump of the ink supply and has a fluid outlet for the dispensing of ink from the ink supply, must be secured to the shell in such a way that it cannot be readily accidentally disengaged therefrom as a result of shock or impact loads. For maintaining resistance to accidental disengagement of any of the elements of the ink supply, namely the shell, the chassis and the cap, from one another, it has been found useful to insert both the chassis and the cap into the shell, with the chassis captured between the cap and the shell.
An ink supply according to the aforesaid pending U.S. patent application Ser. No. 08/429,987 also incorporates a cap of a complex configuration that is secured to the polymeric chassis, after the chassis and the flexible pouch, which is attached to the chassis, is secured to the shell with the flexible pouch contained within the shell. Because of the complexity of the cap, it is preferably formed integrally in a single piece from a polymeric material by injection molding. In any case, it is preferred that the attachment of the cap to the chassis be tamper resistant, which requires a relatively high degree of permanency to such attachment. It has now been found that, in an ink supply with a chassis buried in the shell between the cap and the shell, it is beneficial to sonically weld the cap to the shell, and this can be done by providing the cap with one or more ledges, which act as energy users.
Accordingly, it is an object of the present invention to provide an improved liquid containing and dispensing device. More particularly, it is an object of the present invention to provide an improved device of the foregoing character that is useful in containing and dispensing ink in an ink-jet printer.
It is also an object of the present invention to provide a liquid containment and dispensing device with an improved volumetric efficiency. More particularly, it is an object of the present invention to provide an improved device of the foregoing character that is useful in containing and dispensing ink in an ink-jet printer.
It is also an object of the present invention to provide a printing ink containment and dispensing device having improved resistance to disengagement of the elements thereof under shock or impact load.
It is also an object of the present invention to provide a printing ink containment and dispensing device with good tamper indicating properties.
For a further understanding of the present invention and the objects thereof, attention is directed to the drawing and the following brief description thereof, to the detailed description of the preferred embodiment of the invention, and to the appended claims.